Abstract -
The process to discover and extract useful information is web usage mining. It helps to better understand and achieve the needs of web-based applications. To enhance the efficiency and to ease of the mining process, the data should be preprocessed. The proper study and analysis of web log file is useful to manage the websites effectively for administrative and userâ€™s perspective. Many a time the backward referencing used to track the reachability of the pages which consumes time and generates complete path from the root node even if the link has come from some other server page. This problem can be using two-way hash table structure as Access History List. In our system, session identification is done using AHL by considering immediate link analysis, backward referencing without searching the whole tree representing the server pages. Based on this study, it can be concluded that the system is complex but user session sequences are generated with less time and greater precision.

Department of Physics, Jahangirnagar UniversityDepartment of APEE, University of RajshahiDepartment of EEE, Bangladesh University

Abstract -
The present paper emphasizes greatly on the development of a simulation model for the single relaying based cooperative MIMO OFDM wireless communication system This paper provides a new insight on system performance comparison with Amplify and Forward relaying protocol, STBC and Spatial multiplexing schemes, four channel equalization techniques (ZF, MMSE, ZF-SIC and MMSE-SIC) and four digital modulation schemes (BPSK, QPSK, 16PSK and 64PSK). From simulation results for encrypted color image transmission, it is observable that the STBC encoded MIMO-OFDM system with Amplify and Forward relaying protocol, BPSK digital modulation and MMSE-SIC channel equalization technique provides an encouraging and quite acceptable system performance.

Abstract -
Three-dimensional (3D) imaging and display have been subjects of much research due to their diverse bene?ts and applications. This paper presents a new approach for decomposing the three-dimensional medical images using Bidimensional Empirical Mode Decomposition (BEMD). The BEMD is an extension of the Empirical Mode Decomposition (EMD), which can decompose non-linear and non-stationary signals into basis functions called the Intrinsic Mode Functions (IMFs). IMFs are monocomponent functions that have well defined instantaneous frequencies. This decomposition, obtained by a process known as sifting process, allows extracting the structures at different scales and spatial frequencies with modulation in amplitudes and frequency. BEMD decomposes an image into bidimensional BIMFs. This paper suggests a simple, but effective, method for decomposing a three-dimensional medical image into basis function. This approach is neither parametric nor data driven, which means it does not depend on a priori basis set. Moreover, it preserves the totality of information in term of the quality of the reconstructed 3D image. The performance of this approach, using the BEMD, is approved with some medical images.

Abstract -
Stethoscope become standard equipment used medical personnel to perform initial checks on patients. Stethoscope in general has a function for auscultation, which is listening to the sounds that occur in the body. The sound produced by the biological activity of the bodys organs, like the heart, lungs and digestive system. The heart is one organ that plays a role in the circulatory system. Contraction of the heart that can cause pulsation felt in the arteries in some places. Instrument used for the detection of clinically sound heart is an acoustic stethoscope. Acoustic stethoscope has a weakness, depending on the hearing of each physician. Diagnosis of each physician may vary. Sensitivity of the ear of each doctor is different. Noise signals generated in the electronic stethoscope will be analyzed using Wavelet. In this research, recognition of heart sounds using a stethoscope sound signal based on wavelet decomposition. Heart sound signal is decomposed up to level 8 using Daubechies3 wavelet (db3). Energy of each subband is calculated spectogram. Analysis of cardiac auscultation signals with wavelet daubachies, system can calculate the value of heartrate with 78% for heart sound pattern of early and late systolic murmur, 63% Diastolic heart sound patterns Rumble and 85% for normal heart sound patterns.

Index
Terms -
Wavelet, Stetoschope, Heartrate

Performance Assessment of DFT-OFDM and DWT-OFDM Systems in the Presence of the SSPA and Fading Channel

Abstract -
This paper investigates performance degradation of conventional Orthogonal Frequency Division Multiplexing (OFDM) and Discrete Wavelet Transform based OFDM (DWT-OFDM) systems when the signals are passed through a nonlinear High Power Amplifier (HPA) and fading channel. In the case of DWT-OFDM, several wavelets such as Daubechies, Symlet and Biorthogonal are evaluated. Simulation results in terms of PAPR, PSD, and Bit Error Rate (BER) show that DWT-OFDM is more robust against interference and multipath effects compared to DFT-OFDM, and increasing the length of the basis function improves BER and PAPR.

Abstract -
Today malware threats represent the greatest challenge to information security. Combat between malware writer and malware researcher never end. Malware writers use a variety of avoidance techniques such as Code Obfuscation, Packing, Anti-Debugging and Anti-Virtualisation Technologies to foil researchers analysis. On behalf of researchers they try to find out many techniques to defend Information Technology (IT) services from access or stolen by unauthorized parties. Most of the researches perform malware analysis in Virtualisation Technology in the isolation environment because of security issues. This research focuses on analysis malware using static method in operating system environment. Thus, we focus on malware analysis that uses Anti-Virtualisation avoidance technique. Although our platform environment exposed to the threat by malware sample, we protect this environment by using Toolwiz TimeFreeze and window backup image to protect and secure our environment. This research proved that our environment capable to do malware analysis and compare our environment with the virtual machine environment to prove that our analysis more accurate.

Abstract -
A wireless sensor network (WSN) has important applications such as remote environmental monitoring and target tracking. In addition, Wireless Sensor networks is an emerging technology and have great potential to be employed in critical situations like battlefields and commercial applications such as building, traffic surveillance, habitat monitoring and smart homes and many more scenarios. One of the major challenges wireless sensor networks face today is security. This has been enabled by the availability for a kind of possible attacks; the innate power and recall limit of sensor nodes earn customary security solutions unfeasible. These sensors are equipped with wireless interfaces with which they can communicate with one pther to form a network. In this paper we present a survey of security issues in WSNs, address the state of the art in research on sensor network security, and discuss some future directions for research.